1. Field of the Invention
The present invention relates to a vacuum lamination system and a vacuum lamination method, in which after a laminate film and a laminate base item are laminated, the laminate film is cutoff from the laminated item having the laminate film laminated thereon.
2. Description of Related Art
As the technique for laminating a laminate film such as NCF to a laminate base item such as semiconductor wafer and then cutting the excessive portion of the laminate film off the wafer having the laminate film laminated thereon, it has been known that the techniques described in Japanese Patent Application Laid-Open (JP-A) No. 2009-32853 (0017 to 0019, FIG. 1), JP-A No. 2002-134438A (0045 to 0049, FIGS. 11 and 13) and so on. According to JP-A No. 2009-32853 (0017 to 0019, FIG. 1), the adhesive sheet is directly cut in accordance with the shape of wafer by the cutting blade at the position where the adhesive sheet is pressed and adhered to the wafer. In JP-A No. 2009-32853 (0017 to 0019, FIG. 1), however, the position where the adhesive sheet is pressed to a wafer and the position where the adhesive sheet is cut are the same, and a cutting unit is disposed at the outer peripheral side of the pressing unit. Therefore, limitations are imposed on the pressing of the adhesive sheet to a wafer or constraints are applied to the cutting of the excessive portion of the adhesive sheet from the wafer having the adhesive sheet adhered thereto. Specifically, as described in FIG. 1 of JP-A No. 2009-32853 (0017 to 0019, FIG. 1), the portion to be cut by the cutting unit is positioned in the outside of the area to be pressed and adhered by the first rubber-like pressing unit. Therefore, in JP-A No. 2009-32653 (0017 to 0019, FIG. 1), while air between the adhesive sheet and the wafer is expelled, at the portion closer to the outside of the wafer, by the rotatably moving press roller, the adhesive sheet and the wafer are affixed. In the method for affixing an adhesive sheet to a wafer in two stages as described above, however, it cannot be expected that the adhesive sheet is affixed uniformly to the entire surface of the wafer. Further, in JP-A No. 2009-32853 (0017 to 0019, FIG. 1), there is no description that pressing by an elastic rubber sheet is performed in a vacuum state, and it is not expected that use of a press roller leads to a good affixation with air being completely expelled.
In JP-A No. 2002-134438 (0045 to 0049, FIGS. 11 and 13), a die bond tape is affixed to a wafer using an application roll on a wafer mounting table, and after the application roll is moved, the tape is, in the same position, cut by the cutting blade in accordance with the shape of the wafer. In JP-A No. 2002-134438 (0045 to 0049, FIGS. 11 and 13), however, affixation of wafer is performed by the application roll, and there have been problems described below. There has been a problem in which since the application roll can compress only a limited area at a time, a high-pressure compression is partially applied to a wafer. In addition, there has been a problem in which when pressure is applied to a round-shape wafer from one side toward the other side by the application roll, the compression force applied by the application roll differs among at the starting portion, the ending portion and the middle portion because the length of compressed wafer is differed. Furthermore, the application roll moves from one side toward the other side of the wafer surface, and in the case where a wafer has projections such as bumps, a lateral force is applied to the wafer and the projections fall down.
In recent years, there have been cases in which laminations under stricter conditions than the conventional lamination conditions are required, such as lamination of film to wafers having fine projections such as bumps, lamination of film to wafers which are much thinner than conventional wafers or lamination to conventional wafers requiring a higher precision and uniform quality without void. But in some of the above cases, the conventional laminating devices cannot fully satisfy the conditions. Therefore, use of a batch type vacuum laminating device as described in JP-A No. 2008-272899 (claim 1, FIG. 1) for lamination of wafer has been considered. In the case of JP-A No. 2008-272899 (claim 1, FIG. 1), a continuous belt-shaped material to be laminated and a laminate material are laminated by the vacuum laminating device while being sandwiched between the upper and lower carrier films, and then the upper and lower carrier films are delaminated. Thereafter, the belt-shaped laminated item is cut in a predetermined length.
It is difficult, however, to use the vacuum laminating device and the cutting device of JP-A No. 2008-272899 (claim 1, FIG. 1) for lamination of wafer and cutting of film, because of the reasons described below. In the case of lamination of wafer, round-shape wafers are conveyed one by one. Therefore, the process described in JP-A No. 2008-272899 (claim 1, FIG. 1), by which only the belt-shaped laminated item is taken out and cut after the carrier film is delaminated, cannot be used. In addition, it may be possible to move wafers having film laminated by the vacuum laminating device of JP-A No. 2008-272899 (claim 1, FIG. 1) to the cutting device disposed at a different position by another conveying device different from a carrier film, but disposition of another conveying device is disadvantageous in terms of cost and space.
Furthermore, the laminate base items in the above-described configuration are not limited to wafer but include other non-continuous, single-body laminate base items (such as circuit board). The similar problems occur in cutting of the excessive portion of the laminate film from the laminated circuit board after lamination by the batch type vacuum laminating device is completed.